High frequency resistive switching behavior of amorphous TiO₂ and NiO

Area of Science:

• Materials Science
• Solid State Physics
• Electronics Engineering

Background:

• Resistive switching (RS) in Transition Metal Oxides (TMOs) is key for next-gen non-volatile memory and high-frequency wireless communication (e.g., 6G).
• The RS mechanism is linked to conductive filament formation/rupture, but not fully understood.
• Amorphous Titanium Dioxide (TiO2) and Nickel Oxide (NiO) are investigated for their switching behaviors.

Purpose of the Study:

• To compare the DC and high-frequency switching characteristics of amorphous TiO2 and NiO.
• To elucidate the conduction mechanisms in these binary oxides.
• To assess their suitability for emerging memory and 6G mm-wave applications, including a Reflective-Type Variable Attenuator (RTVA).

Main Methods:

• DC electrical measurements of amorphous TiO2 and NiO devices with varying active region lengths.
• High-frequency characterization of switching performance.
• Design and testing of a 15 GHz RTVA utilizing TMOs.

Main Results:

• DC resistance of TiO2 was independent of active region length, unlike NiO where resistance decreased with increased length.
• TiO2 demonstrated significantly better high-frequency switching performance (lower insertion loss in ON state, higher isolation in OFF state) than NiO.
• The developed RTVA achieved a dynamic range of at least 18 dB with a maximum insertion loss of 2.1 dB.

Conclusions:

• The findings enhance understanding of conduction mechanisms in binary oxides.
• TiO2 shows superior potential over NiO for high-frequency applications like 6G.
• TMOs are viable for advanced electronic devices, including high-performance variable attenuators.